Nocturnal symptoms of asthma such as coughing, wheezing, dyspnoea and dyspn
oea on awakening are common in children with asthma. This is an important i
ssue since nocturnal symptoms may have a negative influence on the child's
life, affecting, for example, school performance or quality of life. Only a
minority of the patients report their nocturnal symptoms spontaneously. Do
ctors should therefore specifically ask if a child is experiencing such sym
ptoms. Nocturnal airflow limitation, induced by an increase in inflammatory
activity, is thought to be responsible for these symptoms. Several other f
actors, both endogenous and exogenous, contribute to this fall in lung func
tion. Therapeutic regimens aim to reduce inflammation and the subsequent co
nstriction of the smooth muscle cell. Environmental measures, like smoke av
oidance or house dust mite reduction, can reduce the exposure to exogenous
triggers, while inhaled medication acts specifically on the inflammation or
smooth muscle cell constriction. Treatment with inhaled corticosteroids; h
as a positive influence on lung function and the degree of bronchial hyperr
esponsiveness. Since short-acting bronchodilators provide dilation for only
4 to 6 hours, their role in the treatment of nocturnal symptoms is less im
portant, especially in children. Long-acting bronchodilators, such as susta
ined release theophylline, have been shown to improve nocturnal symptoms an
d (nocturnal) lung function. However, the small therapeutic range of those
agents with respect to plasma concentration is a complicating factor for tr
eatment of children with asthma. Long-acting beta(2) agonists have a positi
ve influence on nightly awakenings and lung function. Some studies indicate
, however, that the combination of a long-acting beta(2) agonist with an in
haled corticosteroid is superior to long-acting beta(2) agonists alone.